An engine may operate at excessive speeds which may result in causing damage. There may be known systems which limit the speed at which the engine operates. The known systems may respond to a signal indicative of engine speed in order to prevent the engine from operating at a speed in excess of a predetermined threshold value.
U.S. Pat. No. 4,090,480 may describe an electrical control system for preventing the speed of an engine from exceeding a predetermined value. The control system may include a reversible motor connected to an engine throttle control. A motor control circuitry may be connected so as to receive an input corresponding to the speed of the engine. When the speed of the engine exceeds the predetermined value, the control circuitry may actuate the throttle control to limit the engine speed to the predetermined value.
U.S. Pat. No. 4,964,385 may describe an engine over speed control circuit for a multicylinder internal combustion engine. The over speed control circuit may progressively cut out ignition to the cylinders depending upon the amount the threshold is exceeded. A monostable multivibrator may be set by the ignition pulse of a given cylinder to initiate a given timing interval of fixed duration. A charging capacitor circuit may have a first capacitor charged by the output of the monostable multivibrator during the timing interval, and discharged during a second timing interval until the next ignition pulse of the given cylinder. A latching comparator may be set by the ignition pulse of the given cylinder and may disable a cut-out switch which in turn permits ignition pulses to the cylinders. As engine speed increases, the ignition pulses of the given cylinder may be closer in time, and the second timing interval may be a lesser fraction of the time between ignition pulses of the given cylinder, such that the discharge time of the first capacitor becomes shorter, and the voltage on the first and second capacitors begins to increase along a positive slope ramp from a higher minimum, such that the voltage on the second capacitor reaches the threshold voltage at an earlier time following the ignition pulse of the given cylinder.
The present disclosure is directed, at least in part, to improving or overcoming one or more aspects of the prior art system.